Roadway.



No. 748,248. PATENTED DEC. 29, 1903.

w WILSON ROADWAY.

APPLICATION TILED JUNE 12.1903.

N0 MODEL.

("lbw/" ofims PETER" co. momum on WASHINGTON u c UNITED STATES Patented fiecember 29, 1903;

PATENT OFFICE.

ROADWAY.

SPECIFICATION formingpart of Letters Patent No. 748,248, dated December 29, 1903.

Application filed June 12, 1903. $erial No. 161,145. (No model.)

T0 at whom it may concern.-

Be it known that I, WILLIAM WILSON, a citizen of the Unitied States, residing at Geneva, Ontario county, New York,have invented certain new and useful Improvements in Roadovercome many of the objections to both.

The invention consists of a roadway havin g alayer of comparatively largeirregularlyshaped stones laid adjacentto each other with one broad flat face of each lowermost, having the upper surfaces of said stones coated with a bituminous substance, having the apices of the angular spaces between said stones filled with a mixture of a bituminous substance with sand and stone screenings, tamped in place, and having the remaining portions of the spaces between said stones filled with tarred niacadam material, consisting of stones coated or mixed with a bituminous substance, the said macadam ma terial being sujected to compression to force and hold the same in place.

The invention also consists in the novel method of laying the roadway, as will be more fully hereinafter described and claimed.

In the drawing forming part of this specication the figure thereof is a cross-sectional view of a portion of a roadway constructed in accordance with my invention.

In carrying out my invention the road-bed 1 is formed by suitably grading the earth between the curbs, and on this bed is placed by hand a layer of comparatively large stones 2, varying somewhat in size from six to twentyinches in length, from four to eight inches in width, and from six to ten inches in height. These stones are taken just as they come from the quarry, and each is laid on the bed with one of its flatsides lowermost. "Afterward, each of the stones 2, which go to make up the foundation layer, is coated with tar or other bituminous substance, as indicated by the numeral 3. This bituminous substance may be applied either by sprinkling the same on said stones or by sweeping it thereon,

through the agency of a broom. When the stones 2 have been laid as described, the

apices of the angular spaces 4 between them i are filled with a mixture of tar or other bituminous substance and sand, stone screenings, or the like, which mixture is carefully tamped into place. When this has been done, the remaining portions of the spaces between said stones are filled with tarred macadam material-that is, a mixture ofbroken stones, preferably from one-half inch to two and onehalf inches in size,and tar or other bituminous substance, together with a substance such as sand,stone-dust,orscreenings. This material constitutes afiller 5 and extends up to a point in line with or slightly above or below the tops of the stones 2. The same is tamped into place and afterward it is further com pressed, as by passing a heavy roller over the same. The rolling process will cause slight depressions to be formed between the tops of the adjacent stones 2, but tends to thoroughly and completely compact the mass between said stones. When the rolling operation has been efi'ected, a layer 6 of tarred macadain material exactly the same as the material 5 is placed upon the upper surface of the roadway as thus far completed and is thoroughly rolled and compacted. The result isthat the upper surface of the roadway will be evenly arched or leveled with no danger of the formation of pockets or recesses for the reception of water afterward. A thin top dressing 7 of a bituminous substance mixed with sand, stone screenings, or the like may be laid upon the upper surface of the layer 6 for the purpose of forming a smooth and finished condition to the upper surface of the completed roadway.

It has been stated heretofore that the tiller 5 of tarred macadam material is composed of comparatively small stones mixed with tar or other bituminous substance and sand, stone-dust, or screenings. I do not limit myself, however, to any particular size of stones or even to small stones. Large stones coated or mixed with a bituminous substance may be employed inserted into the spaces between the stones 2 of the foundation. The filler made of the large stones need notcome up to the tops of the stones 2, or it may project above the same. The large stones of which the filler is made may be placed in position by hand or by other means; but all the spaces lCO between the same and the sides of the stones 2 should be filled either with a very fine tarred macadam material or with the same substance that is employed in filling the apices'of the angular spaces 4.

The coating of the stones 2 with the laye 3 of tar or other bituminous substance serves to effect a complete and lasting bond between said stones and the tarred macadam filler 5. Furthermore, as the stones 2 are laid with one fiat face of each lowermost the danger of the sinking of the road-foundation into the road-bed is reduced to a minimum. Lateral separation of the stones 2, which constitute the foundation, is prevented by the filler 5 of tarred macadam material, and the said filler 5 also serves to build up and form a stable and reliable body for the road. The fine tarred macadam material is used in the apices of the angular spaces 4 in order to insure a complete filling of said spaces. If the ordinary tarred macadam material of which the filler 5 is made were employed for this purpose, it would in many cases be prevented from penetrating to the extreme lower ends of said spaces by reason of the fact that the stones which form part of said material are too large.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A roadway having a layer of comparatively large irregularly-shaped stones laid adjacent to each other with one broad fiat face of each lowermost, having the upper surfaces of said stones coated with a bituminous substance,having the apices of the angular spaces between said stones filled with a mixture of a bituminous substance with sand and stone screenings, tamped in place, and having the remaining portions of the spaces between said stones filled with a tarred macadam material, consisting of stones coated or mixed with a bituminous substance, the said macadam material being subjected to compression to force and hold the same in place.

2. The method of laying a roadway, which consists in placing a layer of comparatively large irregularly-shaped stones upon a suitable bed, with one broad, flat face of each lowermost, coating the upper surfaces of said stones with a bituminous substance, filling the apices of the angular spaces between said stones with a mixture of a bituminous substance with sand or stone screenings, and tamping it into place, filling the remaining portions of the spaces between said stones with tarred macadam material, consisting of stones coated or mixed with a bituminous substance, and subjecting said tarred macadam material to compression.

3. The method of laying a roadway, which consists in placing a layer of comparatively large irregularly-shaped stones upon a suitable bed, with one broad, flat face of each lowermost, coating the upper surfaces of said stones with a bituminous substance, filling the apices of the angular spaces between said stones with a mixture of a bituminous substance with sand or stone screenings, and tamping it into place, filling the remaining portions of the spaces between said stones with tarred macadam material, consisting of stones coated or mixed with a bituminous substance, tamping and rolling down said tarred macadam material, placing a layer of the same material on top of that previously laid, rolling the latter layer down into place, and finally applying a top dressing or surface coating to complete the roadway.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

WM. WILSON.

Witnesses:

R. A. KANFIELD, O. D. Woonoocx. 

